The present invention relates to a resilient, liner insulation with a polymeric fiber insulation blanket core and to a method of making the resilient liner insulation. The resilient liner insulation exhibits a flame spread/smoke developed index per ASTM E-84-00a tunnel test of ≦ 25/50 and is especially suited for use as equipment and duct liner insulation for HVAC systems.
Glass fiber thermal and acoustical liner insulations are frequently used to line the equipment housings (the housings for air conditioning units, primary fans, etc.) and the air ducts of heating ventilating and air conditioning systems (HVAC systems) to control thermal and/or noise transmission through the walls of these housings and ducts. Glass fiber thermal and acoustical liner insulations are also frequently used to wrap or encase equipment such as dishwashers, refrigerators and other equipment where thermal and/or noise transmission must be controlled. While these glass fiber thermal and acoustical liner insulations perform very well and are quite cost effective when used for these applications, there may be certain applications where it would be desirable to use polymeric fiber liner insulations for lining equipment housings and/or ducts and for insulating appliances and other equipment.
However, to be considered for such applications, any polymeric fiber liner insulation must meet certain performance standards and be cost competitive with the glass fiber liner insulations currently being used for such applications. For use as an equipment housing liner and duct liner in HVAC systems, the polymeric fiber liner insulation should have a major surface over which the gases conveyed within the system flow (the airstream surface) that is tough, durable, puncture resistant, smooth and provided with a porosity that reduces sound transmission through the liner. The airstream surface of the liner insulation should be sufficiently tough and durable to resist puncturing and cracking when being handled prior to and during installation to thereby minimize holes on the interior surface of liner that would adversely affect the air flow through the duct and provide a location for dust, dirt particles, bacteria, mold and the like to collect. The airstream surface of the liner insulation should be sufficiently durable to resist erosion when conveying high velocity airstreams and to permit the cleaning of the airstream surface while the liner insulation is in service. The airstream surface of the liner insulation should have a porosity selected to enhance the sound absorption properties of the liner insulation and to minimize locations where dust, dirt particles, bacteria, mold and the like can collect on the airstream surface. The airstream surface of the liner insulation should be smooth to provide an efficient, low operating cost, air conditioning conveying system. In addition, for use as an equipment housing liner and duct liner in HVAC systems, the polymeric fiber liner insulation should exhibit a flame spread index of 25 or less and a smoke developed index of 50 or less as measured in accordance with the ASTM E-84-00a tunnel test (American Society for Testing and Materials E-84-00a tunnel test) entitled “Standard Test Method for Surface Burning Characteristics of Building Materials. Liner Insulations exhibiting a flame spread index of 25 or less and a smoke developed index of 50 or less, as measured in accordance with the ASTM E-84-00a tunnel test, are hereinafter referred to as having a flame spread/smoke developed index of ≦ 25/50.